Internal-combustion engine.



A. J. MACKAY.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED NOV- 28. I913.

Patented Dec. 19, 1916.

2 SHEETS-SHEET I.

I INVENTOR BY a ONY A. J. MACKAY. INTERNAL comausnou ENGINE.

APPLICATION FILED NOV- ?B. 913.

Patented Dec. 19, 1916.

2 SHEETS-SHEET 2- Fig. 5.

wmx'asszs & a. a.

UNITED STATES PATENT OFFICE.

ALEXANDER JAMES MAGKAY, OF BOURTON, ENGLAND, ASSIGNOB OF ONE-HALF TODONALD NORMAN DODSON, OF WHETSTONE, ENGLAND.

INTERNAL-COMBUSTION Enema.

Specification of Letters Patent.

Patented Dec. 19, 1916.

Application filed November 28, 1913. Serial No. 808,485.

To all whom it may concern:

Be it known that I, ALEXANDER Jams MACKAY, a subject of the King ofGreat Britain and Ireland, residing at Adcroft House, Bourton', in thecounty of Dorset, England, have invented certain new and usefulImprovements in Internal-Combustion Engines, of which the following is aspecification.

This invention relates to internal combustion engines and morearticularly to those of the Diesel and semiiesel types in which air iscompressed to a relatively high pressure com ared with that obtaining inordinarygxp osion engines, and the fuel is then injected into thecylinder or a chamber communicating therewith.

The object of the present invention is to provide an improvedconstruction of cylinder head and neighboring fparts whereby an improvedarrangement '0 jet chamber is provided with a view to obtaining moreperfect scavenging of these parts, more perfect combustion afterinjection of the fuel, more certain ignition on light load and greatereconomy of fuel, and also in the case of a semi-Diesel engine to providefor an improved arrangement and mounting of the hot bulb, whereby it mayretain its heat, be

readily heated and also whereby it may be easily removed for cleaningpurposes.

With these ends in view the principal feature of the present inventionlies in the provision of a cylinder head having a cavity thereincommunicating along one side wit the cylinder and preferably takingroughly the form of an inverted U with bul 'ng sides in cross section,which cavity may orm with the upper end of the piston or a part carriedthereby, a tubular space, at one end of which the fuel inlet jet islocated. The cavity is preferably arranged so that gravity aids thepassage of the fuel along the cavity. This is considered an importantfeature for the reason hereafter set forth.

The cavity is preferably tapered slightly along its length so that thefuel inlet et is arranged at the smaller end thereof, the

widening of the cavity from this point allowing of spreading of the fuelafter leaving the jet. In the case of a semi-Diesel engine in which thecompression temperature of the compressed air is not relied upon forignition but a hot bulb or surface is employed, this surface or bulb isarranged at the end ing washers as hereafter described so that it may bereadil heated and when once hot will retain its eat. I

Reference will now be made to the accompanylng drawings which show twoconvenlent modes of carryin the invention into effect in connection withtwo stroke cycle horizontal and vertical engines of the semi Diesel typein which a. hot bulb or its equivalent is used to aid i nition of thefuel.

In the drawings, igure 1 shows in longitudinal cross section thecylinder head of a horizontal engine to which the invention is applied.Fig. 2 is a sectional view taken on the line 2-2 of Fig. 1. Fig. 3 is asectional view taken in the same lane as Fig. 2 but showing the inletand ex aust ports and the piston at the outer end of its stroke. Fig. 41s a cross sectional view through the inlet and exhaust ports in Fig. 3,while Fig. 5 is a view similar to Fig. 1 but showing by way of examplehow the invention may be applied to a vertical engine. Fig. 6 is adevcloped side view of the ports in the cylinder wall which may beconveniently adopted.

Referring more particularly to Figs. 1 to 4 of the accompanyingdrawings, a indicates a portion of the cylinder wall, 6 indicates thecylinder head which is shown as a se arate casting, which it will beunderstood is suitably bolted to the cylinder, while a indicates thepiston. The cylinder head is pro vided with a cavity (5 which incross-section is in the form of an inverted U with bulging sides, thatis to say the cross-section corresponds substantially with that of theouter cover of an ordinary pneumatic tire. This cavity is taperedlongitudinally, one end being of greater diameter than the other.

n the form shown the cavity though generally of tapering formationhasnot a uniform taper, but as will be seen the rate of the taper isgreatest near the smaller end after which the rate of increase of thesize of the cavity becomes less toward the larger end. In the cavityshown in Fig. 5 this formation is more pronounced and in this case thecavity, though of greater diameter at the inlet end, has actually itslargest dimensions near the middle. In the narrow end of the cavity thefuel inlet jet 6 is arranged so that the fuel may enter the cavity anthe end of the piston a and be sprayed along the length thereof towardthe wider end. In the latter end of the cavity and opposite the fuel jetan opening is provided communicating with the ignition bulb f which ispreferably seated between non-conducting soft washers g and kept inplace by a suitable clamping evice such as the ring it which is situatedbehind the bulb as shown. By this means the bulb is easy to heat andretains its heat better when the engine has been started and theblow-lamp or the like used for initial heatin of the bulb has beenextinguished. Besi es this the bulb, it will be seen, me be easilyremoved for cleaning and provl es 9. ready means of cleanin thecombustion chamber as most or all 0 any unburnt fuel or residue remainsin the bulb.

The axis of the cavity d is preferably arranged substantially verticallyor at a substantial angle to the horizontal and so that the fuelinlet-end is at the higher level. By these means we insure that the fuelmay properly traverse the cavity even when the guantity of fuel admittedis small, since the uel is aided by gravity. Further it is thus insuredthat the fuel, however small in amount, will reach the hot bulb and thuskeep the same hot. Certain ignition is thus obtained even on light loadand there is a minimum of waste. In the case of a horizontal engine theabove mentioned disposition of the cavity may be readily obtained byarranging the same at right angles to the axis of the cylinder and withthe fuel inlet at the top. This arrangement is clearly shown in Fig. 1.In the case of a vertical engine a similar eflect may be obtained byinclining the jet chamber or cavity with respect to the axis of thecylinder as will be presently described in connection with of thedrawings. i

haflle member is provided. in the form of a transverse rib 2' whichextends into the open bottom of the cavity in the cylinder head when thepiston is at the inner end of its stroke, the sides of the rib beingsloped toward the apexof the rib which may be substantially straight andhence substantially. at right an les to the axis of the cylinder,considering t e case of a horizontal engine. One side of the rib, viz:that which is on the same side of the engine cylinder as the exhaustport In in the cylinder walls, is gently sloped as at 7' while theopposite side is sloped abruptly as at Z.

In the side of the cylinder wall con'esponding to this latter abruptlysloped side of the rib on the piston, the air inlet port m is provided;the arrangement being such that when the end of its stro e air enteringthe cylinder will be directed upwardly by the abrupt wall of the baiiiemember into one side of the cavity in the cylinder head, sweeping theiston is at or near the outer ignition space is thus insured. The pathof the air when thus scavenging the cylinder and cavit d is shown by thecontinuous arrows in ig. 3. It will be seen that the end of the abruptlysloped side or wall Z of the rib z is slightly turned over at 1' towardthe wall of the cylinder, thus insuring that the air will be'directed inthe desired manner.

When the piston is at the inner end of its stroke the rib thereon entersthe open portion of the cavity in the cylinder head and as previouslymentioned a tubular space is thus formed as shown in Figs. 1 and 2.

Referring to Fig. 5 which shows by way of example how the invention maybe a plied to an engine having a vertical or (iiagonal cylinder withoutsacrificing the help of gravity in aiding the pasage of fuel to thebulb,"the cavity (1 is here shown as inclined at a substantialinclination and with the jet e at the upper end. The cylinder head I;inclosing the cavity or chamber d is in this case shown as beingintegral with the cylinder but it may of course be made as a separateelement. In order that the baflle member 2' preferably adopted upon thecylinder as before may inclose a tapering tubular space, it is, in theexample shown, sloped to'correspond with the slope of the cavity :3.Otherwise the bafile member is similarly formed and performs the samefunctions as that already described in connection with Figs. 1 to 4. I a

It will be understood that it is not essential toprovide an inclinedcavity as just described. If such a cavity is not desired the cavity maymerely be arranged as in Fig. 1,

so that its axis is substantially at right angles to the cylinder.

. n order that the top of the piston and baflle member may, when at theinner end of the stroke, form as perfect a tapering cavity as possible,it will be seen 4 which shows the piston head in plan, that the rib withits sloping side j forms a tapering trough, one wall of which (viz: thaton the inlet port side) is higher than the other, (see Fig. 2). Toconform to the-she of this trough and the shape of the cavlty d theinlet and exhaust openings are arranged as shown in Fig. 3, so that theyextend around the cylinder nearer one another upon the side thereof, inline with the smaller ends of the trough and cavity. That is thedistance between the ends of the ports at s, t is less than at u, o.This arrangement has an advantage in that the larger beari surfacebetween a and '1: may be arrange on the side of the cylinder which takesthe thrust. This is a feature of importance since some types of enginewear badly adjacent the'ports if these are on the thrust from Fig.

side of the cylinder, since the ports scrape the'oil oil the piston onthe side where it is -most needed.

In place of employing ports as shown in Fig. 4, which are parallel tothe axis of the cylinder, the ports ma be conveniently arrangeddiagonally as own for example in the developed view'shown in Fig. 6,where it will be seen that the orts on each side of the central port areinclined. Such an arrangement has the advantafge of providing a betterbearing surface or the piston and also we consider an easier path forthe scavenging air.

- In operation the fuel entering at the small end of the tubular spacetravels down or along the space and part enters the ignition bulb whichcauses this portion to lfllt9, the flame so produced being reflected aigniting the remainder of the fuel as it enters.

Theignition cavity with'the fuel inlet at one end thereof and whichpreferably tapers outwardly from this end is also applicable to anengine of the ordinary Diesel type though in this case, of course, theignition bulb will not be required.

It is to be understood that the invention is not limited to the exactdetailed arrangements described, as modifications may be made within thespirit of the invention.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent is V 1. In an internal combustion engine, acylinder, a combustion chamber arranged across the end of the cylinder,said combustion chamber having a cavity which tapers gradually alon itslength so that one end is of greater iameter than the other, an openingalong one side of the chamber for afiording communication between thecavity and the cylinder,'a piston in said cylinder having a troughshaped end portion which is tapered to corres ond with the taper of thecavity and whic when the piston is at the inner end of its stroke,serves to close ck and the opening between the cavity" and the cylinder,and means for admitting fuel at the smaller end of the ta ering tubulars ace formed by the cavity an the said end 0 the piston, so that thefuel may be sprayed along said 5 ace-toward the lar er end.

2. n an internal com ustion engine, a c linder, a tapering elon tedcombustion c amber disposed lengthwise across the end of the cylinderand communicatin therewith along one side, means for a mitting fuel atthe smaller end of the combustion chamber and-ignition means at thelarger end thereof facing the fuel inlet.

3. In an internal combustion engine, a cylinder, :1. cylinder headhaving an elongated cavity therein tapering longitudinally and disposedlengthwise across the end of the cylinder, said cavit communicatingalong one side with the cy inder, a piston in said cylinder having atapering trough shaped portion which, when the piston is at the innerend of its stroke, servesto close the said opening and completes thetapering cavity so as to rovide a tapering tubular space in the cylinderhead, means for admitting fuel at the smaller end of the space soformed, and ignition means at the larger end of the cavity.

4. In an internal combustion engine, a cylinder, a tapering elongatedcombustion chamber disposed lengthwise across the end of the cylinderand communicatin therewith along one side, means for a mitting fuel atthe smaller end of the combustion chamber and i itionmeans at the largerend thereof facing the fuel inlet, the end of the chamber at which theignition means are arranged being lower than the end at which the fuelis admitted.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ALEXANDER JAMES MAOKAY.

Witnesses:

- D. W. DoesoN,

P. A, DUTHUAITE.

